Grinding and smoothing machine for glassware



June 2, 1925. 1,540,474

F. L. HITCHQOCK GRINDING AND SMOOTHING- MACHiNE FOR GLASSWARE Filed July14. 1922 r 3 Sheets-Sheet 1 INVENTOR. i fb/iwasr LH/rcficocw.

I BY N a g WM A TTORNEYS.

June 2, 1925. 1,540,474

F. L. HITCHCOCK I GRINDIM} AND SMQQTHING MACHINE FOR GLASSWARE 511 l15}, 1922 3 Sheets-,Sheet 2 v f h A TTORNEYS.

June 2, 1925.

F. L. HITCHCOCK GRINDING AND SMOOTHING MACHINE FOR GLASSWARE Filed July14. 1922 .3 Sheets-Sheet u INVENTOR. a fafifsfL/flrtl/COCK; j

BY N

' ATTORNEYS,

Patented June 2,1925.

A 1,540,474 'r OFFICEQd ronnnsrn'rrrrcnoocx, on innrannroms, mmnnn,nssrenon '10 THEMARIETTA MANUFACTURING COMPANY,

OF INDIANAPOLIS, INDIANA, A CORPORATION.

GRINDING, AND SMOOTHIHG IMACHIN'E- FOR GLAS'SWARE.

Application filed July 14, 192.2. Serial No. 574,968.

To all whom it may camera:

Be it known that I, Forum-s1 L. HITCH- coon, a citizen of the UnitedStates, and a resident of Indianapolis, county of Marion, and State ofIndiana, have invented a certain new and useful Grinding and SmoothingMachine for Glassware; and I do hereby declare that the following is afull, clear, and exact description thereof, reference being had to theaccompanying drawings, in

which like numerals refer to like parts.

This invent-ion relates to a grinding and smoothing machine for grindingand smoothing the curved edge of a circular glass plate whereby saidedge will be finished in a true circle for use principally as tabletops, round mirrors, windows and the like.

One feature of the invention resides in the pneumatic means for securingand clamping the plates in position for the grinding and smoothingprocess and thereafter relieving the same for removal from the machine.

Another feature of the invention resides in the means for centering theplates be tween the clamping members, whereby their annular edges may bethe grinding element.

Another feature of the invention relates to the mechanism for rotatingthe carriage whereby the glass plates will be first presented to thegrinding element and thereaf tor presented to the smoothing elementafter the edges have been ground.

Still another feature of the invention relates to the driving mechanismfor rotating the clamping members and glass plates secured thereby atonespeed as they are presented to the grinding element, at another speedas they are presented to the smoothing element, and brought to restafter having been smoothed for permitting their removal from themachine.

Other features of the invention reside in the driving mechanism for thegrinding and smoothing elements and the adjustments and associated partsof themachine, as will be hereinafter more fully described and claimed.

The full nature of this invention will be understood from theaccompanying drawings and the following description and claims.

In the drawings Fig. 1 is a side elevation of the machine. Fig. 2 is aplan view looking down thereon. Fig. 3 is an end elevaupper. ends of theshafts there are properly presented to I power or driving end thereof.Fig. 4 is an end elevation with parts removed and in partial crosssection, showing the means Fig. 5 is an enlarged sectional view on theline 55 of Fig. 1.

In the drawings there is shown an automatic grinding and smoothingmachine supported upon the legs 10, upon which is mounted a frame 11.Rotatably and cen trally mounted upon the frame, there is a carriage ortable 12 which carries about'its periphery a plurality of verticallyextend ing shafts 18 supported beneath the carriage at their lower endby the bearing plates 14 mounted upon the depending brackets 15 whichare secured to the under side of said carriage. The shafts 13 carryfriction disks 16 slidably keyedthereto, and extend upwardly through thecarriage and the bearings 17 mounted thereon. Upon the keyed the lowerclamping members 18 upon which the glass plates 19 are supported when inposition.

"Mounted directly above the lower clamping members 18 there is an upperclamping member 20 supported by ingarms 21* carried upon the center ofthe carriage 12. Mounted upon said armsin alignment with the clampingmembers 20 there air cylinders 22. The shafts 23 upon which the members20 are rotatably mounted, extend upwardly into the air cylinders 22 andhave secured on the upper ends thereof tion showing the taken plunger-s24. Mounted between the plunger and the bottom of the air cylinder thereis a compression spring 25 surrounding the shaft 23 for normally liftingthe member 20 and holding it open in spaced relation to the member 18,as shown in the left hand side of Fig. 1. The central cylinder 22, shownin Fig. 1, is broken away to disclose the plungers 24 and spring 25.Connected with the top of the cylinders 22 there are compressed airpipes 26 which are controlled by the two way cocks 27. Bymeans of thisarrangement when the glass is positionediand adjusted upon the lowerclamping member 18, the operator moves the cock 27,0pening the same,closing it to the atmosphere, and permitting the compressed air to forcethe.

upper. member 20 down on to the glass so as V to clamp the same thereon.When the for revolving the table. a I

the radially extenda centers of the uppers are compressed smoothingprocess has been completed, the operator'turns the cook 27 so that itcloses the compressed air pipe and opens to the atmosphere, whereby thespring 25 will raise the member 20 and permit the removal of the glass.plate.

The glass plates 19 are positioned upon the clan'iping members 18 sothat their centers are substantially coincident by means of theadjusting lingers 28 mounted upon the sleeves 29 which are slidablymounted upon the rectangular bar frame 30 supported by the arms 21,there being two sleeves and lingers upon each side of the clampingmembers, as shown in 2. The sleeves 29 are caused to slide back andforth upon the frame by means of the hand wheel 31 which is providedwith a pinion mounted in engagement with the rack bars 32 secured to andslidable with the sleeves 29. This construction causes the sleeves 29and lingers 28 to slide back and forth to and from center upon theturning of the hand wheel 31. In a smuch as the arms 28 are providedwith downwardly extending engaging lugs 83 on each end, said lugs willbe brought into engagement with the periphery of the glass plate as thehand wheel is turned. in theproper direction so as to center said plateupon the clamping member with respectto the four points of contact. Itwill be understood that the plate has been previously broken off roughlyin a substantially circular form. After the plate has been centered onthe clamping member and the top clamping member brought down intoclamping engagement therewith, the hand wheel 31 is turned for causingthe release of the peripheral edge of the glass plate so as to permit itto freely rotate with the clamping members, as will be hereinafterdescribed. The arms 28 have the downwardly and rearwardly extendingportions which are pivotally mounted upon the pin 34 so as to be.adjustable to plates with edges of varying curvatures. Afterthe arms 28are properly positioned with respect to each other they are secured inrigid connection by the lock nuts 34 For driving the machine, there isprovided a motor 35 mounted upon the frame at one end of the machinewhich,-through the gear 36 drives the chain 37 which in turn drives thegear 38. The gear 38 is keyed upon the shaft 39 which extends throughsuitable bearings in the frame and upon which is secured the grindingelement 10, whereby said driving element will be driven by the motor.Keyed upon the shaft 89 there is a pulley 11 which drives the belt 12which in turn drives the pulley 43, asshown in Fig. 3. The pulley 43 ismounted upon the shaft 14' mounted in the bearings {15 inthe frame .ofsaid machine and having on one end thereof a beveled mounted in thebearings 49.

gear 46 adapted to mesh with the bevel gear 1-? which is keyed upon theshaft 48 Upon one end of the shaft &8 there is a pulley 50 for drivingthe belt 51. i

For rotating the clamping members 18 and 20, and the glass plate clampedtherebetween, there is provided a friction disk 52 keyed upon the shaft53 extending longitudinally through the frame of the machine and mountedin the bearings 5 1. On the opposite end of the shaft 53 from thefriction disk 52 there is secured a worm gear 55 adapted to mesh withthe worm 56 on theshaft 48, whereby said worm gear and friction disk areslowly rotated through the driving mechanism above described. As thecarriage 12 is turned so thatone of the friction wheels 16 come incontact with the friction disk 52, as shown in Fig. 1, the clampingmembers and-glassfplate are slowly rotated about the center of theirshaft 13 sothat the edge of the glass plate is brought into contact withthe rapidly rotating grinding element 40. The grinding element therebygrinds off the rough edge of the glass plate as it is slowly rotated bythe mechanism above described. It will be noted that the glassplate isonly rotated when the carriage is moved to bring it into position sothat its friction wheel 16 will be in frictional engagement with thedisk 52.

The pulley 50 and belt 51 drive the pulley 5'] which is directlyconnected with the friction disk 58 mounted on the shaft 59 supportedbythe bearings 60. Upon the completion of the grinding process thecarriage is revolved so that the friction wheel 16, which has been inengagement with the disk'52, is moved out of. engagement therewith andinto engagen'ient with the friction disk 58. The glass plate is thenrotated at a high rate ,of speed with its ground edge in engagement withthe smoothingblocks 61, whereby the ground edge is smoothed and madeready for polishing.

The smoothing block 61 is secured within the holder 62 which ispivotally mounted on the arm 63 andheld in adjusted position withrespect to the curvature of the edge of the plate glass by the setscrews 6 1. The arm 63 is mounted upon a shaft 65 which extendsdownwardly in the bearing support 66 which is held in vertical positionby the bracket 6'1 secured to the frame of the machine. upon the arm 63and yieldingly holding the smoothing block in engagement with the edgeof the glass plate, there is provided a rod .68 secured at one end tothe frame and extending through a lever 69 on the shaft For exerting ayielding pressure on the endof said rod. For increasing the pressure ofthe smoothing block against the.

edge ofthe glass plate, the nut 71 is screwed on the rod against thespring, and for decreasing the pressure said nut is screwed in theopposite direction for releasing the spring. The vertical adjustment ofthe smoothing stones is obtained by means of a lever 72 which ispivotedintermediate its ends upon the bracket 73 and is provided with aprojection 7% on one end adapted to extend slightly into a recess in thelower end of the shaft 65. Between the lower end of the bearing support66 and a collar 75 there is a spring 76 for normally maintaining theshaft and arm 68 in lowered positron. Engaging the other end of thelever 72 there'is a rod 77 which extends vertically as shown in Figs. 1and 3 into engagement with the lever 7 8 which is fulcrumed intermediateits ends to the frame of the machine. The opposite end of the lever 7 8,as shown in dotted lines in Fig. 3, is mounted in engagement with thecam 80 mounted on the shaft 53 adjacent-the friction disk 52. Inasmuchas the shaft 53 rotates comparatively slowly, the cam 80 will slowlymove the lever 78 up and down, which in turn will slowly raise the shaft65 and smoothing block 61, and permit the same to be lowered by thespring 7 6. This arrange ment causes a slow vertical reciprocation ofthe smoothing block so as to prevent its wearing out at one portion ofthe surface.

For rotating the carriage upon the frame there is provided a hand wheel81 keyed to the shaft 82 which extends laterally through the lowerportion of the frame and is provided with a worm 83 adapted to mesh withthe worm gear 84, which is keyed to the spindle 85 extending through thecentral portion of the frame and mounted in suitable hearings 86, asshown in Fig. 4. WVhen the operator has set and clamped the plate glassin position he turns the hand wheel 81 so as to cause the machine torevolve until the glass engages the grinding element and is caused toslowly rotate. Upon the entire circumference of the glass plate havingbeen ground, the operator rotates the table, again bringing the glassinto engagement with the smoothing element and a new glass plate intoengagement with the grinding element, which operation is continued aslong as new plates are placed in the machine for grinding.

For varying the diameter of the plates after grinding, and for taking upwear upon the grinding element, said element is mounted upon the slidingcarriage 87 which slides longitudinally upon the cross bars 88 of theframe. For adjusting the position of the grinding element said carriage87 is moved back and forth by turning the hand wheel 89 which is keyedupon the shaft 90 extending laterally through the end of the frame. Theshaft 90' is provided with a worm 91 which meshes with the worm gear 92mounted on the end of the threaded screw 93. Said screw is mounted insuitable hearings in the frame and is adapted to screw throughinternally threaded projections extending from the carriage 87.

In Fig. 6 is illustrated a mounting of the friction wheel 16 upon theshaft 13, whereby it may be adjustable thereon for varying the positionof its engagement with the driving disks 52 and 58. This permits theoperator to so adjust the vertical position of said friction wheels asto vary the speed of rotation thereof with respect to the driving disks.The shaft 13 is hollow and is provided with a vertical anddiametrically. positioned slot 100 through which the inwardly extendingkey portions 101 of the friction wheel 16 are adapted to pass sothatsaid wheel may be vertically slidable upon said shaft and be keyedthereto. For adjusting the vertical position of said wheel with respectto the shaft, there is provided an adjusting screw 102 which extendsinto said shaft and has an adjusting hand wheel 103 on the lower endthereof, said shaft being rotatably seated in the bearing plate 14; bywhich it is fixedly supported, and screwing through the collar 104 whichis formed integral with the portions 101.,

Therefore, upon turning the hand wheel 103 the collar 104- and the wheel16 may be vertically adjusted on said shaft within the limits of theslot 100.

The invention claimed is:

1. A machine for grinding or abrading the circular edge of a piece ofwork, comprising a supporting table, a plurality of clamping membersmounted on said table for clamping said work in position, a grindingelement mounted adjacent said members in position to engage the edge ofthe work for grinding the same, power driven mechanism for rotating saidclamping members, and pneumatic means for forcing one of said clampingmembers against the other under pressure for clamping the worktherebetween and permitting the free rotation thereof.

2. A machine for grinding or abrading the circular edgeof a piece ofwork, comprising a supporting table, a plurality of clamping membersmounted on said table for clamping said work in position, a grindingelement mounted adjacent said members in position to engage the edge ofsaid work for grinding the same, power driven IIgnechanism for rotatingsaid clamping memers, said clamping members against the other underpressure for clamping the work therebetween and permitting the freerotation thereof, and means for releasing the pneumatic means forforcing one of Work and causing said clamping members to separate uponthe pressure of the pneu matic means being cut off.

3. A machine for grinding or abrading the circular edge of a piece ofWork, comprising a supporting table, a plurality of clamping membersmounted on said table for clamping said Work in position, a grindingelement mounted adjacent said members in position to engage the edge ofsaid Work for grinding the same, power driven mechanism for rotatingsaid clamping members, an air cylinder connected With a compressed airpipe having a valve therein, a

thereof reciprocating plunger in said cylinder conne'cted With one ofthe movable clamping members so as to permit the free rotation withrespect to said cylinden whereby upon opening said valve the compressedair Will force said movable clamping member into clamping position, andmeans for returningsaid clamping memher from clamping position upon saidvalve being closed for cutting off the compressed air.

In Witness whereof, I have hereunto afiixed my signature.

FORREST L. HITCHCOCK.

